Pollyanna (noun, adjective)
Pollyanna [pol-ee-an-uh]

noun
1. an excessively or blindly optimistic person.

adjective
2. (often lowercase). Also, Pollyannaish. unreasonably or illogically optimistic: some pollyanna notions about world peace.

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Origin: from the name of the child heroine created by Eleanor Porter (1868-1920), American writer

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